Device for continuously mixing or reacting liquids

ABSTRACT

A device for continuously mixing or reacting liquids has a cylinder with a plurality of spaced radial liquid inlets intermediate its ends for sequentially adding liquid and an outlet. An agitator having two or more shafts disposed parallel with the axis of said cylinder also has a plurality of blades fixed on the respective shafts for extremely restricting the mixture and agitation of the liquids on the axial direction but mainly drives the added liquids radially.

United States Patent 1 1 4 Uchida 1451 Nov; 6, 1973 1 1 DEVICE FORCONTINUOUSLY MIXING on 2,758,915 8/1956 Vodonik 259/104 x I REACTlNGUIDS FOREIGN PATENTS OR APPLICATIONS Inventor; Yosllke UchidarAShigara'679,891 9 1952 Great Britain 259/6 Kamigun, Kanagawa, Japan 536,32612/1955 Italy Assigneez j Photo Film I I 918,932 10/1954 Germany 259/104:32a Ashlgara-Shl Kanagawa 5 Primary Examiner.l0hn Petrakes I 1Assistant ExaminerAlan 1. Cantor .122] Fil d Jun 2, 1971Att0rneySughrue, Rothwell, Mion, Zinn & Macpeak 121 Appl. No.: 149,290

' q [57] ABSTRACT A device for continuous! mixin or reactin li uids 30 FP v y g E q I l J 27:52 only Data J has a cylinder with a plurality ofspaced radial liquid inune apan 4537383 lets'intermediate its ends forsequentially adding liquid and an outlet. An agitator having two or moreshafts $3.8]. p e parallel h i f id cyli d l h 1 'f 259 g 3/08 aplurality of blades fixed on the respective shafts for I 1 o earc 6extremely restricting the mixture and agitation of the- 24 1iquids onthe axial direction but mainly drives the [56] References Cited addedUNITED STATES PATENTS l 4 Claims, 4 Drawing Figures 2,668,756 2/1954Carney 259/6 '.6 4 r pg,

r altar/raj .to uniformly mix and to clean it.

DEVICE FOR CONTINUOUSLY MIXING OR REACTING LIQUIDS BACKGROUND OF THEINVENTION SUMMARY OF THE INVENTION It is, therefore, an object of thepresent invention to provide a device for continuously'mixing orreacting liquids which does-not lose the merits of theconventionalprocess for extremely restricting the extension of thestaying time of the liquids in the device without dif- Generally, inorder to continuously mix or react'liquids so as to obtain uniform andsuperior quality of material, the following points'are considered:

1. Immediately after different types of liquids to be mixed or reactedto each other aremixed, the mixture of the liquids must be made uniform.If there exists partial irregularity of the mixture of the liquids,difference of reacting speeds of the liquids occurs with the result thatit becomes difficult to obtain uniform quality of product.

2. The mixture of the liquids must be completely uniform in compositionuntil the next added solution is applied. This is because the subsequentmixture and reaction of the liquids become irregular with the resultthat the effect of the solution is reduced or detrimental productextremely deteriorates the quality ofthe mixture v ,3. The staying timeof the liquid in the device must not be extended. The extension of thestaying time of the liquids in the device producesthe extension of theperformance distribution of the composition of theliquids passingthrough the device.

The necessity of stable time andthe loss of the products due to theexistence of the transient state at the start-up and before stopping arefrequent troubles in a continuous process of mixing the liquids andexist mostly from the extension of the staying time in the deviceresulting in difficulty of exchange of type of product in the continuousfabricating device.

. Heretofore, if the aforementioned mixture and reaction werecontinuously conducted, there have been used, for example, a continuoustank type in which several mixers and reactors consisting of agitatorsand tanks are disposed serially wherein the tanks are connected in turn;a type in which several pipeline mixers are serially disposed; acylindrical agitator having upper and lower partitions of the agitatingblades for preventing the liquids frommixing reversely by the agitatingblades; or an orifice tower type having aporous plate as a shelf in thecylinder.

The former three types may provide uniform density quickly from themixed liquids and may also mix the solution according to apredeterminedorder, but are difficult due to the increase in the stayingtime of the liquids in the mixer and reactor and the parts-are also.difficult to partiallyclean. 7

The last one of orifice towertype may prevent relatively the extensionof the staying time, but is difficult Thus, these conventional types ofthe mixers and actors are not adapted to a continuous process in'whichuniformity of the quality of product and of mixture are important withthe result that such mixture and reaction must be conducted byfabricating. processes divided into sections.

ficulty'of cleaning and fabrication of mixture.

It is another object of the present invention to provide a device forcontinuously mixing or reacting liquids which has a short timefrom thestart-up to stable state of the process.

According to one aspect of the present invention, there is provided adevice for continuously mixing or reacting liquids which comprises acylinder' having a plurality of liquid inlets and an outlet for mixingor reacting liquids, an agitatorhaving two or more shafts disposedparallel with the axis of said cylinder and also having a plurality ofblades fixed on the respective shafts for extremely restricting themixture and agitation of the liquids in the' axial direction but freelyflowing the liquids radially.

companying drawings,'inwhich:

BRIEF DESCRIPTION OF THE DRAWINGS The other objects, features andadvantages of the present invention will become apparant from thefollowing description taken in conjunction with the ac- FIG. I is alongitudinal sectional view of one embodiment of the device constructedin accordance with the present invention;

FIG. 2 is a sectional viewof the device taken along the line 2-2 in FIG.1; j

FIG. 3 is a view of an agitating blade used in the device formedaccording to the present invention; and

FIG. 4 is a graph showing the extension of the staying time of oneexperiment using the device of this invention. i

Reference 'is now made to the drawings, particularly to FIG. 1,'whichshows one embodiment of the device constructed according to the presentinvention.

Reference numeral 1 illustrates a cylindrical body for I mixing orreacting liquids, 2 a jacket for holding liquid in the body at apredetermined temperature, 3 an axial inlet for a first liquid to bemixed or reacted liquid, shafts 4, 6 and 7 for agitating blades 8 and 9connected to drive means (not shown) such as an electric motor throughmechanical seals or bearings fixed to the upper and lower walls of thecylinder. The agitating blades 8 and 9are thin planar disc shapeforflowing the liquids radially. 10 to 14 show radially disposed addinginlets provided at the side wall of the cylinder for introducingrespectively, other liquids to be mixed with or reacted to the firstliquid in order into the cylinder, 15 is an outletfor discharging mixed'or reactedliquid out of the rection perpendicular to the axis of thecylinder with sufficiently stirring, at the same time, the first liquidis carried to the outlet 15 along the axis of the cylinder as awholenwhileother liquids introduced into the cylaction of agitatingblades provided near respective inlets to 14 and mix with the firstliquid in turn. And, since respective liquids introduced into thecylinder 1 through the inlets 10 to 14 do not flow down in the axialdirection of the cylinder 1 by the action of agitating blades 8 and 9,respective liquids are never mixed in the reverse order and the stayingtime of the liquid in the cylinder 1 is not so extended. Thus, allliquids are mixed uniformly and speedily in predetermined order. In anadditional effect of the device of the present invention, a plurality ofagitating blades provided perpendicularly to the axis of the cylinderfunction to lessen a stationary rotating portion of liquid around theshafts, so that the liquids are further uniformly and effectively mixed.

The device of the invention will now be further described in detail withrespect to its specifications.

The inner diameter of the cylinder may be selected depending upon thetype of reaction, reacting time, treating capacity, etc., and alsodepending upon the number of agitating shafts and the size of theagitating blades. The number of shafts of the agitator must be at leasttwo or more, and may preferably be four. The shape of the agitatingblades must be, for example, of circular disc shape as shown in FIGS. 1and 2 such that the axial mixing and agitating of the liquids isextremely restricted but the liquids to be sequentially mixed are mainlyflowing during mixing in the direction perpendicular to the axis of thecylinder, and the thickness of the blades may preferably be of l to 5mm,the diameter of the blades may preferably be one-fourth to one-half theinner diameter of the cylinder. The distance between the agitatingblades on the same shaft may preferably be 20 to 60 mm. The number ofrevolutions of the agitating blades may preferably be 400 to 500 rpm,and if it is excessively low, the mixing becomes worse, while if it isexcessively high, the staying time of the liquids is extended due tothereverse mixing. The rotating direction of the blades may be in thesame direction, or may partially be in the reverse direction. Thedistance and number of the radial inlets mounted at the wall of thecylinder maybe determined depending upon the number of the solution orliquids and adding capacity and mixing time. There exist some upward anddownward flows near the inlets for the liquids but there exist mainlyradial flows, and if turbine blades superior in spattering force areprovided, the mixing of the liquid,

restriction of the liquid of the upward and downward I flows andprevention of extension of staying time are improved effectively.

In order to further'clarify the features and advantages of the device ofthis invention, the distribution of the staying time and mixture willnow be described with respect to the following examples.

EXAMPLE 1 Conditions of Device:

Diameter of cylinder: 80 mm' Length of cylinder: 2000 mm Number ofagitating shafts: 4 Direction of agitating shafts: the same directionNumber of revolution: I 700 rpm Diameter of agitating blades: 30 mmShape of agitating blades: Circular disc 4 Distance between agitatingblades: Conditions of Liquids:

High polymer solution for photographic photosensitive materialViscosity: 40 CP Specific weight: 1.1 Flow rate: 2000 cc/min. and 5000cc/min.

device of this invention issuch that the device cornprises a pluralityof rotary shafts in a reactor and agitating blades provided on theshafts so that the mixture and agitation of the liquid in the axialdirection are extremely restricted but the radial flow of the liquid isfreely provided in design so as to prevent the upward and downwardmixture of the liquids but to improve the radial mixture. v

Another example of the device of this invention to the fabrication ofsilver halide emulsion for photographic photosensitive material will nowbe described in the following Example.

EXAMPLE 2 Conditions of Device:

Inner diameter of reactor: mm Length of reactor: 1500 mm' Number ofagitating shafts: 4

Rotating directions of the shafts: 2: clockwise 2:

counterclockwise I Number of revolutions: 500 rpm Diameter of agitatingblades: 35 mm Shape of agitating blades: Planar circular disc Distancebetween the blades: 40 mm Conditions of Liquids:

Silver halide emulsion for photographic tive material photosensi-Viscosity: 30 CP Specific weight: 1.2 Flow rate: 3000 cc/min.

Adding organic compounds: three types of methanol solutions Flow rate 50cc/min 300 cc/min.

Inorganic compounds: four types of water solutions Flow rate: 50'cc/min.500 cc/min.

As a result of this experiment, the silver halide emulsion forphotographic photosensitive material which does not produce foreignmaterials due to the reaction of the liquids and which is of highquality is fabricated stably at 30 seconds after starting.

Thus, the present invention provides the effects such that: 1. Uniformmixture of liquids is quicklyobtained.

2. Extension of staying time is lessened so as to provide uniformquality of mixture.

3. Transient losses of the liquid at the starting and stopping areeliminated.

4. Cleaning is easy.

As indicated in FIG. 4, the concentration of the secondary liquidswithin the first liquid-is plotted in terms of the residence time of theliquids within the cylinder for flows in terms of five feet per minuteand two feet per minute, respectively. Where the density reaches orapproaches one, indicative of complete and uniform concentration, whichis the desired end result, there is relatively little extension in thestaying time by the apparatus of the present invention for,particularly, increased flow rates.

What is claimed is:

1. A device for continuously mixing or reacting a plurality of liquidscomprising:

a cylinder having an inlet for receivinga first liquid at one end, andan outlet for discharging the same at the opposite end,

a plurality of axially spaced, radially directed second liquid inlets onthe wall of said cylinder, and being disposed intermediate of said firstliquid inlet and said outlet, and

an agitator comprising at least two rotatable shafts disposed withinsaid cylinder, said shafts extending parallel to the longitudinal axisof said cylinder, each shaft including a pluralityuof axially spaceddisc-shaped blades at respective positions in planes substantiallycommon to the axes of said second liquid inlets,

same plane therewith carrying means for impelling said second liquidsentering the cylinder from said 7 second liquid inlets in a radialdirection relative to I said cylinder to mix said second liquidssequentially with said first liquid; whereby, rotation of said shaftscause mixture and agitation of the liquids in directions radial to thelongitudinal axis of the cyl inder but restricts mixture and agitationof the liquids in an axial direction to effect sequential, complete anduniform mixing of the second liquids with the first liquid in thedirection of said liquid outlet.

2. The device as claimed in claim 1, wherein said means for impellingsaid'second liquids in a radial direction comprises circumferentiallyspaced, radial projections adjacent the peripheries thereof, in the pathof and said disc-shaped blades mounted on said shaft nearest said secondliquid inlets and lying in the the incoming respective second liquids.

3. The device as claimed in claim 2, wherein said shaft nearest saidsecond liquid inlets further carries a plurality of axially spaced,disc-shaped blades at positions intermediate said blades carrying saidimpelling means to further restrict mixing and agitation of the liquidsin an axial direction.

4. The device as claimed in claim 1, wherein said shaft nearest saidsecond liquid inlets further carries a plurality of axially spaced,disc-shaped blades at positions intermediate said blades carrying saidimpelling means to further restrict mixing and agitation of the liquidsin an axial direction.

1. A device for continuously mixing or reacting a plurality of liquidscomprising: a cylinder having an inlet for receiving a first liquid atone end, and an outlet for discharging the same at the opposite end, aplurality of axially spaced, radially directed second liquid inlets onthe wall of said cylinder, and being disposed intermediate of said firstliquid inlet and said outlet, and an agitator comprising at least tworotatable shafts disposed within said cylinder, said shafts extendingparallel to the longitudinal axis of said cylinder, each shaft includinga plurality of axially spaced disc-shaped blades at respective positionsin planes substantially common to the axes of said second liquid inlets,and said disc-shaped blades mounted on said shaft nearest said secondliquid inlets and lying in the same plane therewith carrying means forimpelling said second liquids entering the cylinder from said secondliquid inlets in a radial direction relative to said cylinder to mixsaid second liquids sequentially with said first liquid; whereby,rotation of said shafts cause mixture and agitation of the liquids indirections radial to the longitudinal axis of the cylinder but restrictsmixture and agitation of the liquids in an axial direction to effectsequential, complete and uniform mixing of the second liquids with thefirst liquid in the direction of said liquid outlet.
 2. The devicE asclaimed in claim 1, wherein said means for impelling said second liquidsin a radial direction comprises circumferentially spaced, radialprojections adjacent the peripheries thereof, in the path of theincoming respective second liquids.
 3. The device as claimed in claim 2,wherein said shaft nearest said second liquid inlets further carries aplurality of axially spaced, disc-shaped blades at positionsintermediate said blades carrying said impelling means to furtherrestrict mixing and agitation of the liquids in an axial direction. 4.The device as claimed in claim 1, wherein said shaft nearest said secondliquid inlets further carries a plurality of axially spaced, disc-shapedblades at positions intermediate said blades carrying said impellingmeans to further restrict mixing and agitation of the liquids in anaxial direction.